The present invention relates generally to systems for developing and/or modifying calibration parameter sets for computer controlled internal combustion engines.
It is generally known to electrically control various functions of an internal combustion engine via a suitable processor, computer or controller (hereinafter an xe2x80x9cengine control computerxe2x80x9d). Conventionally, a number of desired engine performance characteristics and control features are specified, and one or more software algorithms are developed therefrom and formed into an engine calibration parameter set, or engine calibration, and this engine calibration is then downloaded into the engine control computer via a suitable service/recalibration tool. Thereafter, the engine control computer is operable to control operation of the engine according to the engine calibration resident therein.
With conventional service/recalibration tools, the tools themselves are typically programmed on a set of calibration rules that define compatibility of the various engine calibration data components, limits and ranges of the calibration data, and so forth. In order to perform a successful engine calibration, the conventional tools must accordingly include a version of the rules that is compatible with the engine calibration programmed therein. Compatible revisions of both the engine calibration parameter sets and the calibration rules must therefore be maintained and matched for subsequent engine calibration procedures.
The present invention provides for an engine calibration development or modification process wherein a master set of engine calibration rules is maintained in a single database within a host computer. Calibration rules checking procedures throughout an engine calibration development and/or modification process are conducted, when possible, by the host computer according to the master set of engine calibration rules resident therein. Engine calibration development and/or modification is generally conducted with the assistance of an engine/calibration development computer separate from the host computer, and at times when the engine/calibration development computer is not connected with, or linked to, the host computer. Calibration rules checking can alternatively be conducted by the engine/calibration development computer using a local set of engine calibration rules. In accordance with the process, this local set of engine calibration rules resident within the engine/calibration development computer is automatically updated upon establishing or re-establishing a communications path between the host computer and the engine/calibration development computer.
The present invention comprises at least one or more of the following features or combinations thereof. A method of developing a calibration parameter set for an internal combustion engine is provided comprising the steps of providing a first engine calibration parameter set to a calibration development computer, modifying in the calibration development computer at least one parameter of the first engine calibration parameter set to form a second engine calibration parameter set, providing one of the second engine calibration parameter set and the at least one modified parameter of the first engine calibration parameter set to the host computer, and conducting in the host computer a first calibration rules check of the one of the second engine calibration parameter set and the at least one modified parameter of the first engine calibration parameter set against a rules check database resident therein.
A system for developing a calibration parameter set for an internal combustion engine is provided comprising a host computer including a first rules check database resident therein, and a calibration development computer configured to modify at least one parameter of a first engine calibration parameter set to form a second engine calibration parameter set, the calibration development computer configured to thereafter provide one of the second engine calibration data set and the at least one modified parameter of the first engine calibration parameter set to the host computer, the host computer configured to conduct a calibration rules check of the one of the second engine calibration data set and the at least one modified parameter of the first engine calibration parameter set against the first rules check database.
These and other features of the present invention will become more apparent from the following description of the illustrative embodiments.